package com.meilai.project.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.http.HttpServletRequest;

/**
 * @author 张驰
 * @date 2020/10/19 10:43
 */
public class IPUtils {
    private static final Logger logger = LoggerFactory.getLogger(IPUtils.class);

    public static String getIPAddress(HttpServletRequest request){
        String ip = "";

        try {
            //X-Forwarded-For：Squid 服务代理
            String ipAddresses = request.getHeader("X-Forwarded-For");

            if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
                //Proxy-Client-IP：apache 服务代理
                ipAddresses = request.getHeader("Proxy-Client-IP");
            }

            if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
                //WL-Proxy-Client-IP：weblogic 服务代理
                ipAddresses = request.getHeader("WL-Proxy-Client-IP");
            }

            if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
                //HTTP_CLIENT_IP：有些代理服务器
                ipAddresses = request.getHeader("HTTP_CLIENT_IP");
            }

            if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
                //X-Real-IP：nginx服务代理
                ipAddresses = request.getHeader("X-Real-IP");
            }

            //有些网络通过多层代理，那么获取到的ip就会有多个，一般都是通过逗号（,）分割开来，并且第一个ip为客户端的真实IP
            if (ipAddresses != null && ipAddresses.length() != 0) {
                ip = ipAddresses.split(",")[0];
            }

            //还是不能获取到，最后再通过request.getRemoteAddr();获取
            if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
                ip = request.getRemoteAddr();
            }

            //logger.info("客户端ip:{}", ip);
            return ip;
        } catch (Exception e) {
            logger.error("获取客户端ip异常,异常原因{}", e.getMessage());
            e.printStackTrace();
            return "";
        }
    }
}
